| 摘要 |
PURPOSE:To minimise the occurrence of malfunction to the waveform distortion of the rise and fall of a signal, by obtaining the pulse duration signal through a comparison between the value obtained by a D/A conversion of an input signal and the charging voltage of constant current of an integral capacitor. CONSTITUTION:A phase control signal S is fetched into a register 11 by an LOAD signal, and at the same time an FF circuit 18 is set at the initial state. Then the terminal Q1' of the circuit 18 is set at a high level. With supply of an SET signal, a gate 12 is opened. At the same time, a constant current circuit 13 is started to start the charging to an integral capacitor. The charging voltage of a capacitor 14 is supplied to one side of a comparator 17, and the voltage S'd corresponding to a digital signal S is supplied to the other side of the comparator 17 after a D/A conversion 15. These voltages are compared through a comparator 17, and the output of the circuit 18 is inverted when the coincidence is obtained in the comparison. Then the gate 12 is closed. |
